Curing of unsaturated polymers and grafting onto unsaturated elastomers is well known in the art. Such prior art produces either a nonrubbery product or a product not obtainable by the easily processable mixes of the present invention.
For example, U.S. Pat. No. 3,791,655 discloses a method for preparing a hard rubber compound by grafting a carboxamide onto polybutadiene in the presence of a free radical initiator. Monomers such as stryrene and vinyl toluene were used to crosslink PVC in U.S. Pat. No. 3,725,714, but here, as in the above aforementioned patent, the product is nonrubbery and the polymer is not a polymer containing randomly distributed sites of conjugated olefinic unsaturation as in the present invention.